More Americans are in the markets than at any point since 2007, but it comes with increasing concerns about the end of this golden age.

What's new: "Never has it been so cheap to put money into the market... Financial advice is easier to get... And advances in technology mean investors can keep tabs on their accounts simply by pulling their phones from their pockets," the AP's Stan Choe notes.

Why it matters: "But it’s also important to remember that many investors, for all their confidence, have a long history of selling and buying at inopportune times."

• "When stocks are soaring, everyone’s happy to pile into the market on the expectation that more gains are to come."
• "When stocks are falling, meanwhile, antsy investors sell their holdings. That may help avoid losses, but it creates a tough decision: when to get back into the market? Many investors who dumped stocks during the Great Recession missed out on the big gains that followed."

Be smart: Trump spent much of 2017 pointing at rising 401ks and stocks. He's cooled on the topic in 2018 as markets have struggled, but it's more relevant than ever with an increasing percentage of Americans entering the market.

Thought bubble from Axios' Dan Primack: "Americans are more in it together. That's the cool thing about the stock market. If it does well, lots of us do well. If only the rich are invested in markets, it matters for fewer."

Go deeper: Read Choe's full AP story

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Build-a-Bear had an idea for a "Pay Your Age" promotion that drew lines so large they had to shut it down:

"Per local authorities, we cannot accept additional Guests at our U.S. Build-A-Bear Workshop locations due to crowds and safety concerns. We have closed lines in our U.S. stores. We understand some of our Guests are disappointed and will reach out directly as soon as possible."

Go deeper: NBC News' Scott Budman captured video from San Jose, where he estimated the line at a more than a thousand.